This hack is also an easy one. In fact this is the very first thing I altered in my first router when I was working on Routerbot v1 and I still remember how my hands were shaking when I used my soldering iron against the fine piece of electronics for the first time … No hand shaking after 8th though as it is very simple. The procedure is documented in many different places all over the Internet. In this blog you can find it here. Couple of notes in addition to that post:

Some models of WRT54G-series have screws in the standoffs. Check what you have in your router under the rubber pads before you try opening it. I have never seen those, but some people had.

The router is ROHS-compliant meaning you need to use a really hot soldering gun to avoid cold joins, especially when you’re solding to the ground pin. I found that butane soldering guns work much better then regular electric, so I used Weller P2K portasol and highly recommend this tool

One more thought about the classical COM port hack is that most people also embed a TTL-RS232 level converter into the router and expose those huge ugly and outdated DB9 ports. In TMHRITWE I soldered the serials to one of the expansion ports and use the level converter externally. This not only saves space in the router, but also saves you money. I hove dozen of devices working with TTL, not RS-232. Why would I solder the converter to each of them? I better expose very simple and small 4-pin connector and use just one converter for all of them.

That’s it and it is a very good soldering lesson. Very basic, very practical and very rewarding.